Aksal/nuttx
3
1
Fork 1
mirror of https://github.com/apache/nuttx.git synced 2026-10-08 23:05:20 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 2

drivers/devicetree: Add a set of commonly used FDT utilities.

Browse source
This commit is contained in:
Stuart Ianna 2024-05-08 12:17:33 +10:00 • committed by Xiang Xiao
parent 297b3b0209
commit c4dbabb1bb
4 changed files with 254 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

114
include/nuttx/fdt.h
View file

@ -28,6 +28,7 @@
#include <nuttx/config.h>
#include <stdint.h>
#include <stdbool.h>
#include <nuttx/compiler.h>
/****************************************************************************
@ -186,6 +187,31 @@ int fdt_get_parent_size_cells(FAR const void *fdt, int offset);
uintptr_t fdt_ld_by_cells(FAR const void *value, int cells);
/****************************************************************************
* Name: fdt_get_reg_base_by_name
*
* Description:
* Get the value of the "reg" property by its offset in the "reg-names"
* property
*
* Input Parameters:
* fdt - The pointer to the raw FDT.
* offset - The offset to the node.
* reg_name - The name of the register
*
* Returned Value:
* The register address determined by its name. Returns 0 if:
* - The reg-names property doesn't exist.
* - The reg property doesn't exits.
* - The reg-names property doesn't contain the "reg_name".
* - The offset combined with the size is larger than the width of the
* "reg" field
*
****************************************************************************/
uintptr_t fdt_get_reg_base_by_name(FAR const void *fdt, int offset,
const char *reg_name);
/****************************************************************************
* Name: fdt_get_reg_base
*
@ -195,13 +221,14 @@ uintptr_t fdt_ld_by_cells(FAR const void *value, int cells);
* Input Parameters:
* fdt - The pointer to the raw FDT.
* offset - The offset of the node
* index - The index of the register in the reg field.
*
* Return:
* The base address of the register space
*
****************************************************************************/
uintptr_t fdt_get_reg_base(FAR const void *fdt, int offset);
uintptr_t fdt_get_reg_base(FAR const void *fdt, int offset, int index);
/****************************************************************************
* Name: fdt_get_reg_size
@ -238,4 +265,89 @@ uintptr_t fdt_get_reg_size(FAR const void *fdt, int offset);
uintptr_t fdt_get_reg_base_by_path(FAR const void *fdt,
FAR const char *path);
/****************************************************************************
* Name: fdt_device_is_available
*
* Description:
* Test if node contains the "status" property with field set to okay or
* ok.
*
* Input Parameters:
* fdt - The pointer to the raw FDT.
* offset - The offset to the node to query.
*
* Returned Value:
* true: The node contains the status propertry, and is set to okay or
* ok.
* false: The node contains the status propertry, but it is set to
* something other than ok or okay.
* Always returns true if the node doesn't contain a status property.
*
****************************************************************************/
bool fdt_device_is_available(FAR const void * fdt, int offset);
/****************************************************************************
* Name: fdt_get_node_label
*
* Description:
* Get the label for a given node. The device tree must be compiled with
* the -@ option in order for the symbol table to be generated.
*
* Input Parameters:
* fdt - The pointer to the raw FDT.
* offset - The offset to the node to query.
*
* Returned Value:
* Node label if found. NULL is returned if no label if found for the given
* node.
*
****************************************************************************/
const char *fdt_get_node_label(FAR const void *fdt, int offset);
/****************************************************************************
* Name: fdt_get_clock_frequency
*
* Description:
* Get the value of the "clock-frequency" value for the given node.
*
* Input Parameters:
* fdt - The pointer to the raw FDT.
* offset - The offset to the node to query.
*
* Returned Value:
* The value of the clock-frequency property of the node. Zero is
* returned if the node doesn't contain a clock-frequency property.
*
****************************************************************************/
uintptr_t fdt_get_clock_frequency(FAR const void *fdt, int offset);
/****************************************************************************
* Name: fdt_get_clock_frequency_from_clocks
*
* Description:
* Get the "clock-frequency" property for the given node, using the phandle
* specified in the "clocks" property
*
* Input Parameters:
* fdt - The pointer to the raw FDT.
* node - The offset to the node to query.
* offset - The offset of the phandle in the clocks property
*
* Returned Value:
* The value of the clock-frequency property of the node, following the
* specified phandle in the "clocks"' property. Returns 0 if:
* - The node doesn't have a "clocks" property
* - The offset given is larger than the length of the "clocks" property
* - The phandle specified by the "clocks" property doesn't contain a
* "clock-frequency" property.
*
****************************************************************************/
uintptr_t fdt_get_clock_frequency_from_clocks(FAR const void *fdt,
int offset,
int index);
#endif /* __INCLUDE_NUTTX_FDT_H */